msem-instigator

Whenever you sacrifice a permanent, Mischievous Maolu gets +1/+1 until end of turn and you gain 1 life.

Glitch {1} (Remove one [restriction] for each time you pay the glitch cost.)
Create a token that's a copy of target [noncreature] permanent [you control].

Counter target noncreature spell. Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Flying
When Elder Roc enters, nourish 1. (To nourish 1, either put a +1/+1 counter on this creature or create a 1/1 white Citizen creature token.)

When Emirik Invigilator enters, exile another target nonland permanent until Emirik Invigilator leaves the battlefield.
Fleeting {1}{W} (You may cast this spell for its fleeting cost. If you do, sacrifice it at the beginning of the next end step.)

Surveil 1, then draw a card. You lose 1 life.
Flashback—{B}, Sacrifice a creature. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

As Amber Hills enters, you may pay 2 life. If you don't, Amber Hills enters tapped.
{T}, Sacrifice Amber Hills: Search your library for a Forest or Plains card, put it onto the battlefield, then shuffle.

Choose creature or land, or choose both if you control a creature with power 4 or greater. Reveal the top five cards of your library. Put all cards revealed this way with a chosen type into your hand and the rest into your graveyard.

Battalion — Whenever Fearsome Army and at least two other creatures attack, creatures you control gain menace until end of turn.

Menace, haste, decayed (This can't block. When it attacks, sacrifice it at end of combat.)
At the beginning of combat on each of your turns, if you have three or more creature cards in your graveyard and haven't controlled a creature named Crypt Gnawer this turn, return Crypt Gnawer from your graveyard to the battlefield.

Whenever you make first contact, Entelan Idealist gets +2/+2 until end of turn. (You make first contact the first time each turn you cast a spell with a name not in your graveyard or control already.)

Flying
Mind's Contagion has haste as long as there are two or more creature cards in your graveyard.
Whenever Mind's Contagion deals combat damage to a player, until your next turn, it gains “Noncreature spells opponents cast cost an additional 2 life to cast.”

Demon spells you cast cost {2} less to cast and an additional 2 life to cast.
Whenever you cast a Demon spell, create a 0/1 black Cultist creature token with “{1}{B}{B}, Sacrifice three Cultists: Create a 5/5 black Demon creature token.”

Flash
When Binding Stones enters, exile target creature with power 3 or less until Binding Stones leaves the battlefield.

Mill three cards, then you may return a land card or a Shaman card from your graveyard to your hand.

Create two 1/1 red Pirate creature tokens. Surveil 1.

Choose one —
• Put a -1/-1 counter on target attacking or blocking creature.
• Scarring Censure deals 2 damage to target attacking or blocking creature.

As an additional cost to cast this spell, discard a nonland card.
Target player reveals their hand. You choose a nonland card from it. That player discards that card.

Menace
Savage Stalker attacks each combat if able.

Spirited (When this enters, you may activate one of its activated abilities without paying its cost.)
Equipped creature gets +3/+2.
Equip {2}

When Viridian Townships enters, create two Idol tokens. (They're artifacts with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)
{2}, Sacrifice an Idol: Draw a card.
{2}, Sacrifice an Idol: You gain 3 life.

When Leads Don't Die enters, mill four cards and you gain 4 life.
At the beginning of your upkeep, you may exile X cards from your graveyard and sacrifice Leads Don't Die. When you do, return target creature card with mana value X or less from your graveyard to the battlefield.

Trample
At the beginning of each combat, you may have Ironhide Bellower deal 3 damage to target creature you control. If you do, Ironhide Bellower gets +3/+0 and can't be blocked by creatures with total power 3 or less until end of turn.

Flash (You may cast this spell any time you could cast an instant.)
Flying (This creature can't be blocked except by creatures with flying or reach.)

Flying, menace, trample
When The Wickerscreech of Gatstaf dies, destroy target nonland permanent an opponent controls.
Foreshadow {13}. This costs {1} less for each nonland card in your graveyard. (You may cast this spell for its foreshadow cost. If you do, also trigger its “dies” abilities when it enters.)